A131907 Integers for which a smaller positive integer exists which has the same sum of cubes of its divisors.

194315, 295301, 2953010, 1181204, 1476505, 1886920, 2067107, 2362408, 2526095, 2953010, 3248311, 3691985, 3838913, 4134214, 4469245, 4724816, 5020117, 5610719, 5635135, 5906020, 6023765, 6496622, 6791923, 7382525, 7677826

Offset: 1

Author

Peter Pein (petsie(AT)dordos.net), Jul 26 2007, Jul 28 2007

Keywords

• nonn

Comments

If i < j and A001158(i) = A001158(j) then j is in this sequence. - Jason Yuen, Sep 22 2024

Examples

			194315 is in this sequence because A001158(184926) = A001158(194315) = 7401260364550416.
		

Links

• Max Alekseyev, List of first 224 pairs A131907(n), A131908(n)

Crossrefs

Cf. A001158, A069822, A131902-A131908.

Programs

Mathematica

First@Transpose[Reap[For[n = 1, n <= 5*10^6, n++, (If[Head[ #1] === tmp, #1 = n, Sow[{n, #1}]] & )[ tmp[DivisorSigma[3, n]]]]][[2, 1]]]

Formula

n-th element of {x>0: there exists a k with 0

Extensions

More terms from Max Alekseyev and Daniel Lichtblau (danl(AT)wolfram.com), Jul 28 2007

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